This got too long for the comment reply but I did want to reply to you @10ofspadess
To start with things I liked, Steve and Dustin's arc was great- its something they both needed, very cathartic and emotional, very well acted by the pair of them and great to see them get the chance to play outside their usual more comedic roles. Lucas as the stalwart protector of Max and their reunion was very sweet. It was nice to see Robin and Vickie in a loving and enthusiastic lesbian relationship, although I didn't appreciate Robin's entire storyline being as a sounding board for Will (although I am glad to see a good gay mentor relationship between the two of them).
I personally think that the show has suffered from both the world and the core cast growing too much. It isn't ideal but it is how a lot of these shows which grow so much end up going. S1 was 3 little kids running around with a superpowered kid looking for their friend, a mom who was pushing through everything to find him, a police chief wanting the truth and some armed teens on a related but separate quest. It was small, it was personal. The stakes have to be increased every season, until it gets to a point like this, and where the original characters are unable to be effective any more. Joyce pushes for the truth, for Will in S1 and for Hopper in S4, but in this season there is nothing for her to push for so she gets sidelined. Hopper, idk if its the problems with the actor or scheduling or the fact that they killed him already or that they committed character assassination since S3, but he also has no use now other than shooting or arguing with El. El is so powerful that they have to either incapacitate her or just have her not there or she'll resolve the entire issue. I genuinely don't know if he was badly directed or if Finn just didn't want to be there because he was given nothing and he gave nothing.
There are also too many characters so roles and scenes need to be spread out. Maybe Mike would have been in a scene but oh, theres nothing for Robin this episode, so she can do it instead. Jonathan could have driven the van with the escaping kids in but Murray is here, guess he can do that.
The Jonathan and Nancy break up was badly done. If interpreted as them deciding to work on themselves and come together again in the future its fine, but the entire goop room was silly (apart from to allow Dustin and Steve's moment).
The Upside Down wormhole does make some kind of sense. They escalate every season so it has reached a point where just another baddie in the upside down isn't big enough, a massive world ending wormhole can make sense, especially since they have mentioned wormholes and travelling between dimensions since S1. The info dump was fine too, in universe only about 6 of them would understand a wormhole and it's consequences so they could explain to the rest of them and the audience at the same time. Its not ideal, but sometimes an info dump is the quickest way to do it. Explaining it at the last minute isn't so odd either, every previous season has had something similar.
I do think Will's coming out scene was very poorly done, it should have been an intimate scene with his mom and brother, and his best friends. I think it has been sweet seeing him come to terms with who he is and accept himself. I think they should have had it happen earlier in the show so he has time to be himself and actually meet someone who isnt an epilogue boyfriend. This person should not be and will not be Mike. I think him realising that his crush on Mike is just that, a crush, its fine, as it is a part of the queer experience I and many other people I know have experienced. He loves Mike, Mike has always been there for him, especially during formative years, so it only makes sense that he would develop his feelings towards him. His talk with Robin made him realise that it wasn't really romantic, it wasn't reciprocated, he'd never been in love before so he didn't know how to differentiate between a deep love for a friend and a romantic love.
There are writing issues but I think that comes from the world and the cast growing too much, as I said. There are pacing issues which come from the same. Characters suffer. Not because huge scenes have been cut but because they no longer have time to write the intimate moments which made this show have such heart at the start. They sacrificed character development for large set pieces and scenes which will make people excited at the trailers. It isn't a conspiracy. Its a show getting too big and the team getting to the end and running out of steam and motivation.
